It is known that a normal or an abnormal modification of proteins, such as post-translational modification, as well change of protein expression, is implicated in the functional control of genetic information and the abnormal functional change of the body, such as diseases.
Extensive efforts have been made to develop new drugs which control the function of phosphorylation-related enzymes, thereby treating relevant diseases. Representative of such drugs is Gleevec, an anticancer agent.
For designing and developing new drugs for protein phosphorylation-related diseases, the phosphorylated proteins must be isolated and fractioned from cells or tissues in so large an amount as to allow study thereon.
Hence, the present invention aims to provide a method for isolating and fractioning phosphoproteins from cells or tissues.